IR 05000461/1990005
| ML20062H330 | |
| Person / Time | |
|---|---|
| Site: | Clinton  |
| Issue date: | 05/31/1990 |
| From: | Schapker J NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION III) |
| To: | |
| Shared Package | |
| ML20062H305 | List: |
| References | |
| 50-461-90-05, 50-461-90-5, NUDOCS 9012040262 | |
| Download: ML20062H330 (6) | |
Text
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. py, 0 !. % 0 i Docket-No 50-461 EA 90-108 lilinois Power Cortpany ATTN: Mr. J. $. Perry Vice President Clinton Power Station Mail Code V-275 Post Office Box 678 Clinton, IL 61727 Gentlemen: This refers to the special safety team inspection conducted by Messrs. P. G. Brochman, P. R. Pelke, and S. P. Ray of this office from May 18 through May 31, 1990, of activities at Clinton Power Station, authorized by NRC Operating License No. NPF-62, and to the discussion of our findings with , you and others of your staff at the conclusion of the inspection. The purpose of this inspection was to review the circumstances surrounding two events.
The first event involved the discovery on May 8,1990, that the installed ' configuration of the bellows on the shutdown service water piping to the , division I and 11 emergency diesel generators (DG) was not consistent with the design configuration (tie rods were missing).
The second event occurred on May.11, 1990. During restoration of the isolation for work on the expansion bellows, the DG heat exchanger shutdown service water outlet valves were not i manipulated correctly resulting in their being shut versus throttled open; , !' consequently, when the division I DG was started for a surveillance test, it , - j-tripped on high temperature two minutes after being loaded.
l The enclosed copy of our inspection report identifies areas examined during the inspection. Within these areas, the inspection consisted of a selective . examination of procedures and representative records, observations, and interviews with personnel.
During this inspection, certain of your activities appeared to be in violation of NRC requirements. You will be notified by separate correspondence of our ' decision regarding enforcement actions, based on the findings of this inspection.
No written response is required, until you are notified of the proposed enforcement action.
' In accordance with 10 CFR 2.790 of the Commission's regulations, a copy of } this letter and the enclosed inspection report will be placed in the NRC Public Document Room.
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Illinois Power Company
. We will gladly discuss any questions you have concerning this inspection.
Sincerely, Edward G. Greenman, Director Division of Reactor Projects
Enclosure:
Inspection Report
No. 50-t.61/90012(DRP)
REGION III== Report No. 50-461/90012(DRP) Docket No. 50-461 License No. NPF-62 > l Licensee: 1111nois power Company 500 South 27th Street Decatur, IL 62525 Facility Name: Clinton Power Station Inspection At: Clinton Site, Clinton, Illinois Inspection Conducted: May 18 - May 31, 1990 Inspectors: P. G. Brochman ' ' P. R. Pelke S. P. R Approved B M. D. La y, f Gl4 Co Reactor Projects Section 3B Dath I Inspection Summary L Inspection from May 18 - May 31, 1990 (Report No. 50 '51/90012(DRp)} Areas Inspected: Special, unannounced safety team inspection by the resident < and region based inspectors of circumstances surrounding two events. The - , first event involved a design deviation which occurred during original
constructic.n, in which tie rods were not installed on bellows which connect ' - the shutdown service water piping to the division I and 11 emergency diesel generators. The second event involved errors in rspositioning the shutdown service water isolation valves for the diesel generator heat exchangers, which had been shut to repair tha bellows described above, and resulted in cooling water to the diesel generators being isolated. Results: Both of. ther.e events were of safety significance. The missing tie rods allowed the bellows to expand beyond the design limits and to induce stresses in the safety-related piping and supports which exceeded American i Society of MecN nical Engineer's Boiler and Pressure Vessel Code limits due to _ thermal and hydraulic forces. The licensee had not yet completed an analysis !- of this evet,t which was to include the added effects of a seismic event which j may have resulted in exceeding code allowable stresses even further. The ? second ev6nt resulted in cooling water to both division I and II emergency ] diesel generators being isolated. The diesel generators would have been } unable to perform their design function, had an actual event occurred, without l rapid operator intervention. The second event was of more concern because it H had.the potTntial to lead to failure of the diesel generators, during an !! actual event (emergency core cooling system actuatien coincident with a loss i! l! "Mdlypl & l ;; g
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' . si of f-site power), unless operator's intervened, The licensee had not yet completed an analysis of this event to determine how long the diesel ' generators cou*iJ have run without the cooling water before being permanently - _ damaged. v,.__ J , k l
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. . , DETAILS 1. Persons Contacted Illinois Power Company (IP)
- J. Perry, Vice President
- J. Cook, Manager - Clinton Power Station
- R. Wyatt, Manager - Quality Assurance
J. Miller, Manager - Nuclear Station Engineering
- F. Spangenberg, Ill, Manager - Licensing and Safety
R. Morgenstern, Manager - Scheduling and Outage Management J. Palmer, Manager - Nuclear Training .J. Palchak, Manager - Nuclear Planning and Support D. Morris, Director - Plant Operations S. Rasor, Director - Plant Maintenance D. Holtzscher, Director - Nuclear Safety
- R. Phares, Director - Licensing
S. Hall, Director - Nuclear Program Assessment K. Baker, Supervisor, I&E Interface
- A. Ruwe, Director, System and Reliability Engineering
.
- R. Gill, Manager, Projects and Assessment
, The inspectors also contacted and interviewed other licensee and
contractor personnel during the course of this inspection. .
- Denotes those present during the exit interview on May 31, 1990.
2. Purpose (71707 & 93702) The purpose of this special team inspection was to review the circumstances surrounding two events. The first event involved the - discovery on May 8, 1990, that the installed configuration of the bellows on the shutdown service water piping to the division I and II emergency- diesel generators (DG) was not consistent with the specified design configuration (tie rods were missing). Second, on May 11, 1990, during restoration of the isolation for work on- the expansion bellows, the DG heat exchanger shutdown service water (SX) outlet valves were not* manipulated correctly. This resulted in the valves being in the shut position, vice throttled open. Consequently, when the division I DG was started for a surveillance test it tripped on high jacket water temperature. The inspectors interviewed operating and technical personnel and management involved in each event. The inspectors developed a chrorology for each event and analyzed each event for its safety implications. .F i
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., - 3. Unanalyzed Condition in Div_ision I and II Emergency Diesel Generators due to Missing Tie Rods on Shutdown Service Water Bellows a. Description of Event On May 8, 1990, the licensee identified that tie rods on bellows connecting the division I and 11 emergency diesel generator heat exchangers to the associated shutdown service water piping were not installed. There was a bellows on both the inlet and outlet SX pipes for each of the two tandem diesel engines on each of the division I and II diesel generators for a total of eight bellows. The bellows were installed to isolate vibratory motion between the SX piping and the diesel generators. The tie rods had been installed by *.he vendor to limit bellows expansion. The licensee determined that the tie rods had been removed by mistake during
original construction in 1985. When the licensee determined that design pipe stress calculations had been based on having the tie rods in place and noted significant lateral expansion of the bellows and visible displacement of the attached SX piping, they declared both the division I and II diesel generators inoperable due to being in an unanalyzed condition. The licensee commenced a controlled ' shutdown of the reactor in accordance with Technical Specification Action 3.8.1.1.g and declared a Notification of Unusual Event (NOVE). Hot Shutdown was achieved and the NOUE was terminated on May 9, 1990, b. Sequence of Events Early 1985 Various construction travelers were issued documenting removal of what were apparently thought to be temporary attachments and shipping lugs from the bellows during installation of the bellows in the , SX piping.
i May 2, 1990 The diesel generator system engineer identified that one of the bellows on the division I diesel had a small leak, Conditic, Report 1-90-05-017 was initiated. The condition was determined to have no , impact on system operabiUty.
May 3, 1990 Repair options for the leakii'q bellows were evaluated. A Parker bellows, procured to replace the existing Pathways bellows was located onsite but was not a like-for-like replacement. Field Alteration package SXF018 was initiated to analyze the Parker bellows and authorize its use.- c May 4, 1990 As part of the design work for Field Alteration SXF018, an engineer did a field check of the as-built dimensions of the bellows. He found that the leaking bellows was longer than the original length shown on the vendor's drawing. He also noted that the existing Pathway bellows did not have tie rods,
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. . although the replacement Parker bellows did. Discussions were held with the vendor to try to determine the significance of the missing tie rods and an investigation was initiated to find documentation justifying the removal of the tie rods. The licensee stated that the vendor indicated that the tie rods were not required but were recommended. A review of Seismic Qualification package SQ-CL204 for the bellows did not mention whether tie rods were installed in the qualification tests. May 7, 1990 Engineering measurement of other uninsulated bellows showed them to be extended laterally. A maintenance work request was initiated to remove insulation from the remaining bellows. The bellows on the division III diesel generator were noted to have their tie rods installed. The bellows vendor started to perform stress calculations for se as found bellows dimensions. s:. My 8,1990 8-12:00 a.m. After insulation removal, Engineering took ' measurements of the remaining bellows and forwarded the information to the vendor. The vendor provided design approval for the stretched bellows but recommended that tie rods be installed. . Sargeet and Lundy Engineers, Inc. (S&L) were asked to foreally check the pipe stress calculations. A mainten.nce technician identified that one of the SX piping struts on the division I diesel generator was bent. l Baldwin Associates Construction Travelers were located that authorized the removal of the lugs for [ the tie rods because the lugs were assumed to be lifting lugs for shipping purposes. 2:00 p.m. S&L stated that their original pipe stress design calculations were based on having the tie rods in place. S&L-and Illinois Power engineers started walking down both the division I and II diesel generator SX piping systems to look for damage. 2:10 p.m. Condition Report 1-90-05-028 was writter to ' document the missing tie rods. The Shift Supervisor considered the operability-of the diesels unknown pending completion of the S&L evaluation. i
. . ! ( . . . , ., _ - Field walkdowns noted that the division 11 SX pipe was raised off its sliding support. Condition Report 1-90-05-029 was written to document bent strut and raised support. 5-7:00 p.m. Based on the field walldowns, which also showed that some supports were out of angular alignment, and the fact that S&L piping stress calculations would not be available for two days, a management decision was made to declare both of the diesels inoperable, 6: 40 p.m. The Shif t Supervisor declared both the division I and 11 diesel generators inoperable due to being in an unanalyzed condition. The plant entered the two hour Action requirement of Technical Specification 3.8.1.1.g. The NRC Resident inspectors were notified of the diesel inoperability. 8:40 p.m. A controlled shutdown was started in accordance with Technical Specifications. A NOUE was declared due to commencing a shutdown required by Technical Specifications. 9:21 p.m. The NRC was notified via the Emergency Notification System of the NOVE and shutdown. May 9. 1990 1:00 a.m. The initial S&L pipe stress calculations were completed. 7:26 a.m. The reactor was manually scrammed from about 25% power to complete the shutdown to Operational Condition 3 (Hot Shutdown). 8:00 a.m. The NOVE was terminated. May 10, 1990 The plant entered Operational Condition 4 (Cold Shutdown). c. Evaluation and Analysis . The licensee's response to the event was conservative and in accordance with Technical Specifications. Engineering support in determining the correct configuration of the bellows and in identifying the cause and significance of the missing tie rods was good. Management involvement in the event was very evident. The management decision to declare the diesel generators inoperable was based on the combination of a known deviation from t.he design and observed piping displacement and damage to a support. Later analysis showed that code allowable yield stresses may have been
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. exceeded at some points in the SX piping system, although the licensee determined that actual yield stresses were not exceeded based on a review of the certified material test reports for the components in those areas. This event was considered to be potentially safety signif; cant because the division I and 11 diesel generators had a design deviation that had existed since initial plant licensing, that could have allowed the required SX piping systems on both diesels to fail. However, the licensee determined that the actual piping system materials would not have failed under normal operating conditions because the materials had higher than code required yield strengths. Whether the SX piping systems could have failed under seismic conditions was still to be determined. The root cause of the design deviation appeared to be a misunderstanding of the purpose of the tie rods during initial construction. The rods were apparently thought to be shipping bars , and the lugs were thought to be lifting lugs. These devices were i removed after the bellows were installed. Similar rods on the ! division III diesel generator were not removed. However, the , ' [ division III diesel generator was installed at a different time than divisions I and II,
i Contributing causes for the event were inadequate drawings and instructions from the vendor. The installation instructions portion of the Pathway vendor manual had a sketch of a bellows with shipping bars and lifting lugs. The drawing did not show tie rods. Associated installation instructions did not mention the existence of tie rods but did say to remove the shipping bars af ter installation. In addition, of the 46 safety-related bellows in the plant, only those bellows on the diesel generator service water piping were designed to'have tie rods. There were no tie rods on any other safety-related j bellows.
The licensee had performed an analysis of all safety-related bellows R in response to Violation 461/82020-01-in early 1983. That analysis ' concluded that tie rods were required on the diesel generator SX bellows. However, at that time, the bellows had not been installed, so a field verification of the tie rods could not be done. 10 CFR 50, Appendix B, Criterion III, " Design Control," required, -in part, that measures be established to assure that applicable regulatory requirements and the design basis, are correctly translated into specifications, drawings, procedures, and instructions. Adequate measures were not established during construction of the division I and II diesel generators and their associated shutdown service water
- piping systems in or about 1985 to assure that she requirement for
the installation of bellows tie rods required by the design basis was correctly translated into installation drawings and instructions. As a result, the division I and II diesel generator service water piping systems did not meet their design basis requirements from 1y
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, - .. the date of issuance of the low power license on September 29, 1986, until May 8, 1990. This is an apparent violation of 10 CFR 50, Appendix B, Criterion III (461/90012-01(DRP)). d. Licensee's Corrective Actions The inspectors attended the licensee's critique of the event and followed the licensee's corrective actions throughout the event. Major corrective actions consisted of the following: (1) The division I and 11 diesel generators were declared inoperable and the actions of Technical Specification 3.8.1.1 were carried out. (2) A NOUE was declared when the shutdown was started and the NRC was notified. The NOVE was terminated when the plant reached Hot Shutdown. The licensee submitted letter U-601671 to the NRC on May 15, 1990, as a summary report of the NOVE. (3) Stress analysis was performed for the bellows with no tie rods to determine worst case (without seismic) loads on the piping system. That analysis identified five piping system areas where code allowable yield stresses could have been exceeded. Those five areas were compared to the certified material test reports to verify that actual material yield stresses would not have been exceeded. (4) Walkdowns were conducted to identify all a nas which appeared to be displaced. Analysis was conducted for all questionable fot ndations, supports, embedments, auxiliary sted, etc. All aress were evaluated as acceptable.. . (5) The leaking bellows was replaced with the Parker bellows conta;ning tie rods. The other seven bellows were returned to ' their duign configuration with lugs and tie rods installed. , (6) Twenty-six pipe supports were adjusted to design alignment
' tolerances. One support could tiot be returned to tolerance and j was evaluated as acceptable. The bent pipe strut was replaced and other repairs were made to correct minor deficiencies in ~ piping supports. (7) Engineers observed piping movement during initial system pressurization.to assure that no excessive displacement occurred. l. (8) The licensee intended to submit a Licensee Event Report to- the NRC within 30 days of the event. (9) The licensee was reviewing the safety significance of-the missing tie rods under expected operating and seismic loads. . This evaluation was expected to be completed by June 15, 1990. I h i l ' ' l
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[ l . . an . . ' . ' . 4. Diesel Generator Heat Exchanger SX Isolation Valves Incorrectly - Repositi.oned Af ter Maintenance Which Resulted in a Lack of Cooling Water to the Division I and 11 Diesel Generators a. Description of the Event . To provide isolation for the work on the bellows described above, the licensee danger tagged shut the SX inlet and outlet isolation valves to the division I and 11 diesel gen?rator heat exchangers. The inlet valves for each of the four heat exchangers were normally used as throttle valves to regulate flow. The valves were 1/4 turn butterfly valves with geared handwheels which required several turns to open the valve. The valves were also used to provide isolation for the maintenance on the bellows, Valves ISX005A & B, ISX064A and ISXO65B had caution tags hung on them which indicated the throttle position of each valve. These positions had been determined previously by the SX flow balancing (see inspection report i 461/9006(DRS)). Duririg the process of flow balancing the SX system, the licensee's +";nnical staff developed a methodology to position the throttle velves so as to obtain consistent flow rates. This method involved turning the valve handwheel until evidence of stem movement or flow past the valve seat was noted and then, while opening the valve,
counting the number of turns open until the desired throttle position was reached. This technique was in contrast to one in which the number of turns open from "hard" shut were counted (i.e., from the beginning of handwheel movement). This second technique was found to not be repeatable enough to allow for accurate flow - balancing, due to considerable slack in the gear train for the valves (more than one full turn of the handwheel). When the SX valves were repositioned after maintenance o6 the
- j bellows, the incorrect method (the second technique above) was i utilized. Since the' positions stated on the caution tags were all . roughly one turn open, except for valve ISX0658, the net effect was - that the valves remained closed. The licensee started up the reactor
j and entered Operational Condition 2 (Startup) at 10:40 a.m. on May 14, i 1990. At 1:35 p.m. on May-15, 1990, the division-1 diesel generator J was started for a routine surveillance. Two minutes after reaching full load, at 1:47 p.m., the diesel tripped on high jacket water i temperature due to a lack of cooling water. . I b. Sequence of Events March 19, 1990 Caution tagout 90-0213 was issued for division I - j. of the SX system and each tag specified the throttle
position for its associated valve based on the ' initial flow balancing. Division I of.the SX system was taken out of service to perform a modification to achieve proper flow balancing. In addition to stating the valve's position, the caution tags stated that they should remain in place until the permanent ] valve lineup for SX was revised. ": l
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I ~ (" . , ... March 22, 1990 Division I of SX was restored to operation and a . final flow balancing was performed. As a result, the i throttle positions for valves ISX005A and ISX064A were changed; however, the caution tags were not revised to indicate the new throttle positions. April 07, 1990 Caution tagout 90-0302 was issued for division II of SX and utilized interim positions for valves 1SX005B and ISX065B. The caution tags were annotated with words similar to division I regarding removal. A ril 16, 1990 A memorandum was sent from the plant technical J staff to the operations department which contained the final, correct, positions for all throttle valves ' in SX divisions I, II, and III. This information was not incorporated into caution tagouts 90-0213 and 90-0302.
May 9,1990 The SX throttle valves for the division I and II A diesel generators were danger tagged closed in order l to perform maintenance on the bellows to restore them to their design condition. (F May 11, 1990 Division I and II.SX valves to the diesel generators ji. were restored to their throttle position, in accordance ! with caution tagouts 90-0213 and 90-0302 (incorrect position still specified on the tagouts). This would have resulted in the valves being too far open, which,. while not affecting the diesel generators, could have reduced the flow rates to other SX components. However, ,' an additional error occurred in that the operator who positioned the valves, utilized the wrong methodology (turns open from hard shut vice turns open from valve , disk beginning to move). 'In this event, the operator
had questioned-the assistant shift supervisor on what !j was the correct method to position the throttle valve, i but he received incorrect guidance. As a consequence of.this error, and the slack in the gear train for the valve operator, the SX flow to three of the four diesel engines was isolated, rendering the division I and II diesel generators inoperable. May 14, 1990 The unit was in aperational Condition 4 (Cold Shutdown) and a reactor startup was commenced, Operational Condition 2 was entered at 10:40 a.m. y
May 15, 1990 ' 1:35 p.m. The division I diesel generator was started for a routir.e surveillance. .j 1:45 p.m. -The diesel generator reached rated load. j '
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. - -..... - - -.. - - - ,. .- < , .. - .. 1:47 p.m. The diesel generator tripped on high jacket water temperature due to a lack of cooling. The maximum jacket water temperature reached was 208 F and the maximum lubricating oil temperature reached was 190 F. 2:00 p.m. The low flow condition was identified and division I valves ISX005A and ISX064A were repositioned to the values specified on caution tagout 90-0213 (an incorrect value). 2:32 p.m. The division 11 valves ISX005B and ISX065B were repositioned to the values specified on tagout 90-0302 (an incorrect value). 6:00 p.m. Valves ISX05A & B, ISX064A, and ISX065B were repositioned to their correct throttle positions after the existing valve positions were reviewed by the technical staff. 8:40 p.m. An operability surveillance was completed satisfactorily . for the division III diesel generator, t. 11:38 p.m. An operability surveillance was completed satisfactorily < for the division II diesel generator. May 16, 1990 6:30 a.m. An operability surveillance was completed satisfactorily for the division I diesel generator. May'26, 1990 A permanent procedure change for the SX system , ' lineup was issued which incorporated the final flow balancing positions. The caution tags were removed. - !- c. Evaluation and Analysis ! Technical Specification 1.27 required,'in part, that a system, subsystem, tnin. component, or device be OPERABLE or have OPERABILITY when-it is capable of performing its specified. function (s) and when all necessary. attendant cooling or other auxiliary equipment that are required for the system to perform its function (s) are also o I capable of performing their related suppt,rt function (s). ,. Technical Specification 3.0.4 required that entry into an. i; OPERATIONAL CONDITION'or other specified condition not be made { unless the conditions for the Limiting Condition for Operation - L are met without reliance on provisions contained in the ACTION
requirements, Technical Specification 3.8.1.1.b required, in part, that three qC separate and independent diesel generators be OPERABLE while in [ OPERATIONAL CONDITIONS 1, 2, or 3. t i ! I
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' (. ( .. . -' c The improper operation of the SX valves resulted in shutdown service water to the division I and II diesel engine heat exchangers being isolated. The SX system directly cools the jacket water system for each engine and indirectly cools the lubricating oil system for each engine (via the jacket water system). With the shutdown service water isolated, the division I engines ran for only 12 minutes, of which 2 minutes were under full load, before tripping on high jacket water temperature on the 16 cylinder diesel engine. With the shutdown service water isolated the jacket water would begin to boil away. The diesel may have been able to continue to operate while the jacket water was boiling. However, when a significant amount of the jacket water was boiled off the cylinder walls, heads, and lubricating oil temperatures would all rise rapidly resulting in failure of the diesel generator when the pistons or bearings seize. Without the necessary support system of shutdown service water the diesel generator could not perform its design function. Consequently, it was inoperable. During normal operations, a high jacket water temperature would trip the diesel generator. However, if the diesel , L generator started under Loss of Coolant Accident (LOCA) conditions, i the high jacket water temperature trip was bypassed. Consequently, l a high jacket water. temperature would not cause a trip but would alarm a specific annunciator at the diesel generator's local control ' panel and a general diesel generator trouble annunciator in the main i cont ol room. With division 1 and II diesel generators inoperable, , i action statement g. of Technical Specification 3.8.1.1 applied. Consequently, entry into Operational Condition 2 was not allowed by Technical Specification 3.0.4. The entry into Operational ' Condition 2 at 10:40 a.m. on May 14, 1990, with division I and II E diesel generators-inoperable, was an apparent violation of Technical Specification 3.0.4(461/90012-02(DRP)), i t .- } At the conclusion of this inspection the licensee had not yet ) established the length of time the diesel generators could operate ! without cooling water. Rapid operator actions would have been - required to restore cooling water to the diesel generators in plE the case of an emergency in which the diesel generators were required to operate. It took approximately 13 minutes from the I time a. diesel generator trouble alarm was received until cooling water was restored to the division I diesel generator during the- event of May 15, 1990. During that event, an operator was present locally at the' diesel. In the case of an unexpected event such a.s a LOCA with a loss of offsite power, operators may not have been able to restore cooling to the diese1' generators in time to prevent engine damage. The problems with the interim versus final valve positions did not- contribute to this event. Nevertheless, it was an indicator of the effectiveness of the licensee's efforts to ensure that the SX system could be restored to a balanced condition following manipulation of the valves. . i >
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I , (, - . .' < ' .r .. ' s d. Licensee's Corrective Actions In response to this event, the li'ensee implemented the following corrective actions: (1) Other tagouts were reviewed to determine if similar problems with throttle valves existed. (2) The SX tagout was compared to the final flow balancing positions to ensure no other problems existed. (3) The DG vendor was contacted to obtain information on actions to be taken to assure the diesel was not damaged. (4) The licensee issued the permanent procedure revision to the r' . valve lineup and removed the caution tags. Additionally, the following long term actions have been identified: (1) Determine a method to ensure long term ;'epeatability of throttling valve positions, f (2) Provide training to operators on this event and methods to be used in throttling these and other valves.
5. . Conclusions Both-of the events described in this eport hk potential safety significance and involved circumstar.ces where ewipmant designed to mitigate the consequences-of accidents could have failed to perform their ' design functions. The actu-1 safety significance of the missing bellows tie rods depends primarily on the results of an analysis of the effects of seismic loads on the SX piping and supports. That analysis was not - complete at the time this report was written. The actual safety . significance of the SX ~ valve mispositioning depends primarily on a determination of the length of time the diesels could have operated } without cooling water and the likelihood of operators.being able to , restore cooling before engine damage occurred. That determination was { also not completed at the time of this report. 6. Exit-Interview (30703) The inspectors met'with the licensee representatives denoted in paragraph 1 at the conclusion of the inspection on May 31, 1990. The inspectors summarized the purpose and scope of the inspection and the. findiigs. The inspectors also discussed the likely informational content i , of th t inspection report, with regard to documents or processes reviewed by tFa inspectors during the inspection. The licensee did not identify any such documents or processes as proprietary. ., , i i . l'
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